Abndoned mineshaft have got fixed loot

Abandoned mineshaft minecart with chest have got fixed loot before first peek in. To reproduce:
Find minecart chest in any abandoned mineshaft, stand next to it, type:

/entitydata @e[r=3] {} 

There should be entitydata lootTable:chests/abandoned_mineshaft with seed of it, but instead there is Items:[] with some items in it.